If you do plan to raise funds online, you need to know about the Charleston Principles, which are non-binding guidelines that the National Association of State Charity Officials created to help states develop their own regulations for online fundraising. The Association of Fundraising Professionals (AFP) summarizes them as follows:

Organizations located outside of a particular state must register if they use their website to specifically target people in that state, or receive contributions from the state on a repeated and ongoing basis or a substantial basis through its website. The Principles don't specifically define "ongoing" or "substantial" -- that's left up to each individual state. Organizations should note that email solicitations automatically trigger registration requirements, just as a letter or fax would. What happens next with the Charleston Principles is currently unclear. States have not shown any special urgency to address this issue, but may begin to in the next couple of years.

The AFP also created Internet Transaction Guidelines to provide basic guidance for members and others who might use the services of an online or similar service provider.